A variety of gravity-based systems have long been used to move waste and/or storm water through management and conveyance systems and on to treatment or storage systems. These management and conveyance systems often require pumping stations to lift the water from a lower elevation to a higher elevation such that gravity can be used to move the waste and/or storm water through the system. Lifting pump stations and systems typically have two major components: (1) a collection or pumping container (also referred to herein as a “pump chamber,” a “collection chamber,” a “wet well collection chamber,” or a “wet well”) for collecting and pumping the water up and out of the pump station; and (2) a valve chamber (also referred to herein as a “valve pit,” a “valve vault,” a “valve vault structure,” or a “valve vault chamber”) for monitoring and regulating equipment, such as a water meter, backflow preventer valve, or a pressure reducing valve.
While pumping stations have long been used to raise waste or storm water to higher elevations within a management and conveyance system, there are serious deficiencies and inadequacies with the prior art pumping systems. The two major components of the prior art systems, the wet well and the valve chamber, are housed in separate structures that must be connected to each other during installation. A significant problem with having two separate structures is that each structure will settle at a different rate and depth, commonly referred to as differential settlement. When differential settlement occurs, the piping between the two structures is compromised resulting in breaks and leaks that require excavating the area around and between the structures to repair the damage and stop the leaks. Even after a break has been repaired, there is still the possibility that the piping will break or leak again in the future.
While the problem of separate water pump station structures can be somewhat addressed by fixedly connecting the two separate structures together with fasteners such as bolts, as was done in U.S. Pat. No. 7,150,290 to Smith (“Smith”), which is herein incorporated by reference in its entirety, the problem of differential settlement can still occur due to the different sizes and depths of the two structures. Smith describes two differently sized structures connected together with fasteners after each structure is manufactured, resulting in a single structure having one shorter half and one longer half. When the soil settles around this structure the soil beneath and around the shorter half will settle differently than the soil beneath and around the longer half causing the structure to tilt to one side and possibly move out of plumb. One other deficiency with the Smith structure is that the valve vault chamber is approximately one half the depth of the collection chamber, which results in space beneath the valve vault chamber that is filled with soil when it could be used to increase the storage capacity of the collection chamber. Additionally, the Smith invention requires additional time, labor, and skill to excavate a hole that is deeper for the longer collection chamber structure and shallower for the valve vault chamber structure. Installation of the Smith invention would require that either the two structures are installed separately and fastened together after being set in the hole, or that the excavation is uneven and at different depths to receive the combined structure. Either installation may result in differential settlement, which may cause the entire structure to tilt out of plumb.
There is, therefore, a need for a new waste and storm water pumping station and system that will facilitate the desired function of pumping water from one elevation to another while eliminating differential settlement and maximizing the storage capacity of the wet well collection chamber.